First, some source:
HTML Code:
http://blog.chron.com/gamedayastros/2009/02/baseball-101-with-astros-gm-ed-wade-split-contracts/
Will split contracts ever be added to OOTP? The math would be easy, $507,500 * (1/183) for 1 day of ML service time; $41,400 * (1/183) for 1 day of minor league service while on the 40-man for the 1st year on the 40-man; and $82,700 * (1/183) for 1 day of minor league service while on the 40-man for 2nd and subsequent years on the 40-man. Minimum salary reflects the new 2015 numbers.
More source :
HTML Code:
http://www.truebluela.com/2014/11/20/7178067/mlb-minimum-salary-2015
The calls already exist as the game records active roster and 40-man roster days for the player's profile.